I switched from DirecTV about a month ago, and I have been very pleased with the Hopper/Joey systems.
Pros:
GUI & Performance - The Dish system responds instantly to remote commands, and the GUI is FAST. FFWD, Rewind, Skip, etc. work perfectly and are vastly smoother than DirecTV's trickplays.
Primetime Anytime - records CBS, NBC, ABC, and Fox in Primetime using just one of the three tuners.
Minimal Lights - There are two small LED's on the front panel of the DVR. No absurd twirling blue lights that have to be dimmed or disabled.
Settings Backup - You can backup your settings to the remote and to the DVR.
PIP/Swap - Was not on my DirecTV system.
Remote Setup - Onscreen setup for remote makes it easier to program the remote for TVs and other devices.
Multi-Channel Recall - Shows last four channels (can be disabled to toggle between channels)
Sling Adapter - Still needs work, but it's handy to have.
Auto-Hop - (New feature) Now the system will offer to automatically skip commercials when viewing recorded PTAT recordings. It's a beautiful thing.
SRS Tru-Volume Audio - Set volume level on program. Commercials will not exceed that level. Nice!
Cons:
No Standby Buffer - Probably to save power and system resources, but there is no immediately accessible buffer when you come out of standby. The system only records when powered on.
No PC Software Playback - DirecTV2PC was great. Sling can get you there, but not nearly as functional as the Cyberlink software was with DirecTV.
Sling uses the LAN connection when it can.
No Live Buffer While Watching Recorded Programs - The live buffer stops when I switch to recorded content. It would be nice if it continued to buffer. You just have to remember to press the record button if you want to continue to see what's in the buffer.
No skip to tick
No bookmarks (I never used them)
No OTA - but I hear it's coming
No Quick Clicks (Quicktune on DTV) - It was there, but as of my latest software version it has been removed.
Overall, I'm still infinitely more pleased with the Hopper/Joey system. Mostly because at the end of the day, the core DVR functions beat the pants off of DirecTV's HR series.